Why my boyfriend always has other girls in mind?

We started out as platonic friends and heaps of fun no hanky panky. He was married but his wife left him for someone else. He was pretty cut up and I helped him recover. We got cosy and he suggested living together in a foreign country as we come from a traditional background and cannot live together in our own countries. I thought it wasn't good to hook up on the rebound but he insisted. I agreed and waited for him to find a job in another country, but he was dragging his heels so I gave him an ultimatum to find a job within 3 months or I would return to my own country. Thereupon I found he was cheating on me online. His excuse - he was not sure about me. Later he admitted that he wasn't really serious about living together and flirting with girls online was an old habit. He said he would change and blubbered on a fair bit saying I should give him another chance. After much soul searching I said okay. Later I found he had been chatting texting calling other girls as well. he has also been lying to me about many other things. But he promised he would change. We flew down to another country and tried to find jobs there. It was a stressful time and he couldn't keep his eyes off other girls - constantly watching and commenting on how sweetly {sic} they walk talk behave, etc. I told him how I felt about that and he did stop. So he is open to suggestions of change. Recently he asked me what I think about him getting married to a local woman just so he can get a pport to stay on. I was furious, he isnt even divorced from his first wife yet, also he obviously doesnt think about the other (mythical) local woman he proposes to marry. What should I do about this guy? He is otherwise kind and caring but seems to use women including me. His response to my flaring up was that he was just making an observation and I needn't take it seriously and if I dont like it he wont think about it??!! I think it may be an indication of things to come. I am in a bit of a hole at the moment as I have spent a lot of time, effort and money to come down to this new country. Dont really know what to do. Stay with him till I find a job then move out, or leave now, or go with the tide. Please advice.